--- /dev/null
+/* crypto/engine/eng_dyn.c */
+/* Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL
+ * project 2001.
+ */
+/* ====================================================================
+ * Copyright (c) 1999-2001 The OpenSSL Project. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * 3. All advertising materials mentioning features or use of this
+ * software must display the following acknowledgment:
+ * "This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ * endorse or promote products derived from this software without
+ * prior written permission. For written permission, please contact
+ * licensing@OpenSSL.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ * nor may "OpenSSL" appear in their names without prior written
+ * permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ * acknowledgment:
+ * "This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This product includes cryptographic software written by Eric Young
+ * (eay@cryptsoft.com). This product includes software written by Tim
+ * Hudson (tjh@cryptsoft.com).
+ *
+ */
+
+
+#include "eng_int.h"
+#include <openssl/dso.h>
+
+/* Shared libraries implementing ENGINEs for use by the "dynamic" ENGINE loader
+ * should implement the hook-up functions with the following prototypes. */
+
+/* Our ENGINE handlers */
+static int dynamic_init(ENGINE *e);
+static int dynamic_finish(ENGINE *e);
+static int dynamic_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)(void));
+/* Predeclare our context type */
+typedef struct st_dynamic_data_ctx dynamic_data_ctx;
+/* The implementation for the important control command */
+static int dynamic_load(ENGINE *e, dynamic_data_ctx *ctx);
+
+#define DYNAMIC_CMD_SO_PATH ENGINE_CMD_BASE
+#define DYNAMIC_CMD_NO_VCHECK (ENGINE_CMD_BASE + 1)
+#define DYNAMIC_CMD_ID (ENGINE_CMD_BASE + 2)
+#define DYNAMIC_CMD_LIST_ADD (ENGINE_CMD_BASE + 3)
+#define DYNAMIC_CMD_DIR_LOAD (ENGINE_CMD_BASE + 4)
+#define DYNAMIC_CMD_DIR_ADD (ENGINE_CMD_BASE + 5)
+#define DYNAMIC_CMD_LOAD (ENGINE_CMD_BASE + 6)
+
+/* The constants used when creating the ENGINE */
+static const char *engine_dynamic_id = "dynamic";
+static const char *engine_dynamic_name = "Dynamic engine loading support";
+static const ENGINE_CMD_DEFN dynamic_cmd_defns[] = {
+ {DYNAMIC_CMD_SO_PATH,
+ "SO_PATH",
+ "Specifies the path to the new ENGINE shared library",
+ ENGINE_CMD_FLAG_STRING},
+ {DYNAMIC_CMD_NO_VCHECK,
+ "NO_VCHECK",
+ "Specifies to continue even if version checking fails (boolean)",
+ ENGINE_CMD_FLAG_NUMERIC},
+ {DYNAMIC_CMD_ID,
+ "ID",
+ "Specifies an ENGINE id name for loading",
+ ENGINE_CMD_FLAG_STRING},
+ {DYNAMIC_CMD_LIST_ADD,
+ "LIST_ADD",
+ "Whether to add a loaded ENGINE to the internal list (0=no,1=yes,2=mandatory)",
+ ENGINE_CMD_FLAG_NUMERIC},
+ {DYNAMIC_CMD_DIR_LOAD,
+ "DIR_LOAD",
+ "Specifies whether to load from 'DIR_ADD' directories (0=no,1=yes,2=mandatory)",
+ ENGINE_CMD_FLAG_NUMERIC},
+ {DYNAMIC_CMD_DIR_ADD,
+ "DIR_ADD",
+ "Adds a directory from which ENGINEs can be loaded",
+ ENGINE_CMD_FLAG_STRING},
+ {DYNAMIC_CMD_LOAD,
+ "LOAD",
+ "Load up the ENGINE specified by other settings",
+ ENGINE_CMD_FLAG_NO_INPUT},
+ {0, NULL, NULL, 0}
+ };
+static const ENGINE_CMD_DEFN dynamic_cmd_defns_empty[] = {
+ {0, NULL, NULL, 0}
+ };
+
+/* Loading code stores state inside the ENGINE structure via the "ex_data"
+ * element. We load all our state into a single structure and use that as a
+ * single context in the "ex_data" stack. */
+struct st_dynamic_data_ctx
+ {
+ /* The DSO object we load that supplies the ENGINE code */
+ DSO *dynamic_dso;
+ /* The function pointer to the version checking shared library function */
+ dynamic_v_check_fn v_check;
+ /* The function pointer to the engine-binding shared library function */
+ dynamic_bind_engine bind_engine;
+ /* The default name/path for loading the shared library */
+ const char *DYNAMIC_LIBNAME;
+ /* Whether to continue loading on a version check failure */
+ int no_vcheck;
+ /* If non-NULL, stipulates the 'id' of the ENGINE to be loaded */
+ const char *engine_id;
+ /* If non-zero, a successfully loaded ENGINE should be added to the internal
+ * ENGINE list. If 2, the add must succeed or the entire load should fail. */
+ int list_add_value;
+ /* The symbol name for the version checking function */
+ const char *DYNAMIC_F1;
+ /* The symbol name for the "initialise ENGINE structure" function */
+ const char *DYNAMIC_F2;
+ /* Whether to never use 'dirs', use 'dirs' as a fallback, or only use
+ * 'dirs' for loading. Default is to use 'dirs' as a fallback. */
+ int dir_load;
+ /* A stack of directories from which ENGINEs could be loaded */
+ STACK_OF(OPENSSL_STRING) *dirs;
+ };
+
+/* This is the "ex_data" index we obtain and reserve for use with our context
+ * structure. */
+static int dynamic_ex_data_idx = -1;
+
+static void int_free_str(char *s) { OPENSSL_free(s); }
+/* Because our ex_data element may or may not get allocated depending on whether
+ * a "first-use" occurs before the ENGINE is freed, we have a memory leak
+ * problem to solve. We can't declare a "new" handler for the ex_data as we
+ * don't want a dynamic_data_ctx in *all* ENGINE structures of all types (this
+ * is a bug in the design of CRYPTO_EX_DATA). As such, we just declare a "free"
+ * handler and that will get called if an ENGINE is being destroyed and there
+ * was an ex_data element corresponding to our context type. */
+static void dynamic_data_ctx_free_func(void *parent, void *ptr,
+ CRYPTO_EX_DATA *ad, int idx, long argl, void *argp)
+ {
+ if(ptr)
+ {
+ dynamic_data_ctx *ctx = (dynamic_data_ctx *)ptr;
+ if(ctx->dynamic_dso)
+ DSO_free(ctx->dynamic_dso);
+ if(ctx->DYNAMIC_LIBNAME)
+ OPENSSL_free((void*)ctx->DYNAMIC_LIBNAME);
+ if(ctx->engine_id)
+ OPENSSL_free((void*)ctx->engine_id);
+ if(ctx->dirs)
+ sk_OPENSSL_STRING_pop_free(ctx->dirs, int_free_str);
+ OPENSSL_free(ctx);
+ }
+ }
+
+/* Construct the per-ENGINE context. We create it blindly and then use a lock to
+ * check for a race - if so, all but one of the threads "racing" will have
+ * wasted their time. The alternative involves creating everything inside the
+ * lock which is far worse. */
+static int dynamic_set_data_ctx(ENGINE *e, dynamic_data_ctx **ctx)
+ {
+ dynamic_data_ctx *c;
+ c = OPENSSL_malloc(sizeof(dynamic_data_ctx));
+ if(!c)
+ {
+ ENGINEerr(ENGINE_F_DYNAMIC_SET_DATA_CTX,ERR_R_MALLOC_FAILURE);
+ return 0;
+ }
+ memset(c, 0, sizeof(dynamic_data_ctx));
+ c->dynamic_dso = NULL;
+ c->v_check = NULL;
+ c->bind_engine = NULL;
+ c->DYNAMIC_LIBNAME = NULL;
+ c->no_vcheck = 0;
+ c->engine_id = NULL;
+ c->list_add_value = 0;
+ c->DYNAMIC_F1 = "v_check";
+ c->DYNAMIC_F2 = "bind_engine";
+ c->dir_load = 1;
+ c->dirs = sk_OPENSSL_STRING_new_null();
+ if(!c->dirs)
+ {
+ ENGINEerr(ENGINE_F_DYNAMIC_SET_DATA_CTX,ERR_R_MALLOC_FAILURE);
+ OPENSSL_free(c);
+ return 0;
+ }
+ CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
+ if((*ctx = (dynamic_data_ctx *)ENGINE_get_ex_data(e,
+ dynamic_ex_data_idx)) == NULL)
+ {
+ /* Good, we're the first */
+ ENGINE_set_ex_data(e, dynamic_ex_data_idx, c);
+ *ctx = c;
+ c = NULL;
+ }
+ CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
+ /* If we lost the race to set the context, c is non-NULL and *ctx is the
+ * context of the thread that won. */
+ if(c)
+ OPENSSL_free(c);
+ return 1;
+ }
+
+/* This function retrieves the context structure from an ENGINE's "ex_data", or
+ * if it doesn't exist yet, sets it up. */
+static dynamic_data_ctx *dynamic_get_data_ctx(ENGINE *e)
+ {
+ dynamic_data_ctx *ctx;
+ if(dynamic_ex_data_idx < 0)
+ {
+ /* Create and register the ENGINE ex_data, and associate our
+ * "free" function with it to ensure any allocated contexts get
+ * freed when an ENGINE goes underground. */
+ int new_idx = ENGINE_get_ex_new_index(0, NULL, NULL, NULL,
+ dynamic_data_ctx_free_func);
+ if(new_idx == -1)
+ {
+ ENGINEerr(ENGINE_F_DYNAMIC_GET_DATA_CTX,ENGINE_R_NO_INDEX);
+ return NULL;
+ }
+ CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
+ /* Avoid a race by checking again inside this lock */
+ if(dynamic_ex_data_idx < 0)
+ {
+ /* Good, someone didn't beat us to it */
+ dynamic_ex_data_idx = new_idx;
+ new_idx = -1;
+ }
+ CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
+ /* In theory we could "give back" the index here if
+ * (new_idx>-1), but it's not possible and wouldn't gain us much
+ * if it were. */
+ }
+ ctx = (dynamic_data_ctx *)ENGINE_get_ex_data(e, dynamic_ex_data_idx);
+ /* Check if the context needs to be created */
+ if((ctx == NULL) && !dynamic_set_data_ctx(e, &ctx))
+ /* "set_data" will set errors if necessary */
+ return NULL;
+ return ctx;
+ }
+
+static ENGINE *engine_dynamic(void)
+ {
+ ENGINE *ret = ENGINE_new();
+ if(!ret)
+ return NULL;
+ if(!ENGINE_set_id(ret, engine_dynamic_id) ||
+ !ENGINE_set_name(ret, engine_dynamic_name) ||
+ !ENGINE_set_init_function(ret, dynamic_init) ||
+ !ENGINE_set_finish_function(ret, dynamic_finish) ||
+ !ENGINE_set_ctrl_function(ret, dynamic_ctrl) ||
+ !ENGINE_set_flags(ret, ENGINE_FLAGS_BY_ID_COPY) ||
+ !ENGINE_set_cmd_defns(ret, dynamic_cmd_defns))
+ {
+ ENGINE_free(ret);
+ return NULL;
+ }
+ return ret;
+ }
+
+void ENGINE_load_dynamic(void)
+ {
+ ENGINE *toadd = engine_dynamic();
+ if(!toadd) return;
+ ENGINE_add(toadd);
+ /* If the "add" worked, it gets a structural reference. So either way,
+ * we release our just-created reference. */
+ ENGINE_free(toadd);
+ /* If the "add" didn't work, it was probably a conflict because it was
+ * already added (eg. someone calling ENGINE_load_blah then calling
+ * ENGINE_load_builtin_engines() perhaps). */
+ ERR_clear_error();
+ }
+
+static int dynamic_init(ENGINE *e)
+ {
+ /* We always return failure - the "dyanamic" engine itself can't be used
+ * for anything. */
+ return 0;
+ }
+
+static int dynamic_finish(ENGINE *e)
+ {
+ /* This should never be called on account of "dynamic_init" always
+ * failing. */
+ return 0;
+ }
+
+static int dynamic_ctrl(ENGINE *e, int cmd, long i, void *p, void (*f)(void))
+ {
+ dynamic_data_ctx *ctx = dynamic_get_data_ctx(e);
+ int initialised;
+
+ if(!ctx)
+ {
+ ENGINEerr(ENGINE_F_DYNAMIC_CTRL,ENGINE_R_NOT_LOADED);
+ return 0;
+ }
+ initialised = ((ctx->dynamic_dso == NULL) ? 0 : 1);
+ /* All our control commands require the ENGINE to be uninitialised */
+ if(initialised)
+ {
+ ENGINEerr(ENGINE_F_DYNAMIC_CTRL,
+ ENGINE_R_ALREADY_LOADED);
+ return 0;
+ }
+ switch(cmd)
+ {
+ case DYNAMIC_CMD_SO_PATH:
+ /* a NULL 'p' or a string of zero-length is the same thing */
+ if(p && (strlen((const char *)p) < 1))
+ p = NULL;
+ if(ctx->DYNAMIC_LIBNAME)
+ OPENSSL_free((void*)ctx->DYNAMIC_LIBNAME);
+ if(p)
+ ctx->DYNAMIC_LIBNAME = BUF_strdup(p);
+ else
+ ctx->DYNAMIC_LIBNAME = NULL;
+ return (ctx->DYNAMIC_LIBNAME ? 1 : 0);
+ case DYNAMIC_CMD_NO_VCHECK:
+ ctx->no_vcheck = ((i == 0) ? 0 : 1);
+ return 1;
+ case DYNAMIC_CMD_ID:
+ /* a NULL 'p' or a string of zero-length is the same thing */
+ if(p && (strlen((const char *)p) < 1))
+ p = NULL;
+ if(ctx->engine_id)
+ OPENSSL_free((void*)ctx->engine_id);
+ if(p)
+ ctx->engine_id = BUF_strdup(p);
+ else
+ ctx->engine_id = NULL;
+ return (ctx->engine_id ? 1 : 0);
+ case DYNAMIC_CMD_LIST_ADD:
+ if((i < 0) || (i > 2))
+ {
+ ENGINEerr(ENGINE_F_DYNAMIC_CTRL,
+ ENGINE_R_INVALID_ARGUMENT);
+ return 0;
+ }
+ ctx->list_add_value = (int)i;
+ return 1;
+ case DYNAMIC_CMD_LOAD:
+ return dynamic_load(e, ctx);
+ case DYNAMIC_CMD_DIR_LOAD:
+ if((i < 0) || (i > 2))
+ {
+ ENGINEerr(ENGINE_F_DYNAMIC_CTRL,
+ ENGINE_R_INVALID_ARGUMENT);
+ return 0;
+ }
+ ctx->dir_load = (int)i;
+ return 1;
+ case DYNAMIC_CMD_DIR_ADD:
+ /* a NULL 'p' or a string of zero-length is the same thing */
+ if(!p || (strlen((const char *)p) < 1))
+ {
+ ENGINEerr(ENGINE_F_DYNAMIC_CTRL,
+ ENGINE_R_INVALID_ARGUMENT);
+ return 0;
+ }
+ {
+ char *tmp_str = BUF_strdup(p);
+ if(!tmp_str)
+ {
+ ENGINEerr(ENGINE_F_DYNAMIC_CTRL,
+ ERR_R_MALLOC_FAILURE);
+ return 0;
+ }
+ sk_OPENSSL_STRING_insert(ctx->dirs, tmp_str, -1);
+ }
+ return 1;
+ default:
+ break;
+ }
+ ENGINEerr(ENGINE_F_DYNAMIC_CTRL,ENGINE_R_CTRL_COMMAND_NOT_IMPLEMENTED);
+ return 0;
+ }
+
+static int int_load(dynamic_data_ctx *ctx)
+ {
+ int num, loop;
+ /* Unless told not to, try a direct load */
+ if((ctx->dir_load != 2) && (DSO_load(ctx->dynamic_dso,
+ ctx->DYNAMIC_LIBNAME, NULL, 0)) != NULL)
+ return 1;
+ /* If we're not allowed to use 'dirs' or we have none, fail */
+ if(!ctx->dir_load || (num = sk_OPENSSL_STRING_num(ctx->dirs)) < 1)
+ return 0;
+ for(loop = 0; loop < num; loop++)
+ {
+ const char *s = sk_OPENSSL_STRING_value(ctx->dirs, loop);
+ char *merge = DSO_merge(ctx->dynamic_dso, ctx->DYNAMIC_LIBNAME, s);
+ if(!merge)
+ return 0;
+ if(DSO_load(ctx->dynamic_dso, merge, NULL, 0))
+ {
+ /* Found what we're looking for */
+ OPENSSL_free(merge);
+ return 1;
+ }
+ OPENSSL_free(merge);
+ }
+ return 0;
+ }
+
+static int dynamic_load(ENGINE *e, dynamic_data_ctx *ctx)
+ {
+ ENGINE cpy;
+ dynamic_fns fns;
+
+ if(!ctx->dynamic_dso)
+ ctx->dynamic_dso = DSO_new();
+ if(!ctx->DYNAMIC_LIBNAME)
+ {
+ if(!ctx->engine_id)
+ return 0;
+ ctx->DYNAMIC_LIBNAME =
+ DSO_convert_filename(ctx->dynamic_dso, ctx->engine_id);
+ }
+ if(!int_load(ctx))
+ {
+ ENGINEerr(ENGINE_F_DYNAMIC_LOAD,
+ ENGINE_R_DSO_NOT_FOUND);
+ DSO_free(ctx->dynamic_dso);
+ ctx->dynamic_dso = NULL;
+ return 0;
+ }
+ /* We have to find a bind function otherwise it'll always end badly */
+ if(!(ctx->bind_engine = (dynamic_bind_engine)DSO_bind_func(
+ ctx->dynamic_dso, ctx->DYNAMIC_F2)))
+ {
+ ctx->bind_engine = NULL;
+ DSO_free(ctx->dynamic_dso);
+ ctx->dynamic_dso = NULL;
+ ENGINEerr(ENGINE_F_DYNAMIC_LOAD,
+ ENGINE_R_DSO_FAILURE);
+ return 0;
+ }
+ /* Do we perform version checking? */
+ if(!ctx->no_vcheck)
+ {
+ unsigned long vcheck_res = 0;
+ /* Now we try to find a version checking function and decide how
+ * to cope with failure if/when it fails. */
+ ctx->v_check = (dynamic_v_check_fn)DSO_bind_func(
+ ctx->dynamic_dso, ctx->DYNAMIC_F1);
+ if(ctx->v_check)
+ vcheck_res = ctx->v_check(OSSL_DYNAMIC_VERSION);
+ /* We fail if the version checker veto'd the load *or* if it is
+ * deferring to us (by returning its version) and we think it is
+ * too old. */
+ if(vcheck_res < OSSL_DYNAMIC_OLDEST)
+ {
+ /* Fail */
+ ctx->bind_engine = NULL;
+ ctx->v_check = NULL;
+ DSO_free(ctx->dynamic_dso);
+ ctx->dynamic_dso = NULL;
+ ENGINEerr(ENGINE_F_DYNAMIC_LOAD,
+ ENGINE_R_VERSION_INCOMPATIBILITY);
+ return 0;
+ }
+ }
+ /* First binary copy the ENGINE structure so that we can roll back if
+ * the hand-over fails */
+ memcpy(&cpy, e, sizeof(ENGINE));
+ /* Provide the ERR, "ex_data", memory, and locking callbacks so the
+ * loaded library uses our state rather than its own. FIXME: As noted in
+ * engine.h, much of this would be simplified if each area of code
+ * provided its own "summary" structure of all related callbacks. It
+ * would also increase opaqueness. */
+ fns.static_state = ENGINE_get_static_state();
+ fns.err_fns = ERR_get_implementation();
+ fns.ex_data_fns = CRYPTO_get_ex_data_implementation();
+ CRYPTO_get_mem_functions(&fns.mem_fns.malloc_cb,
+ &fns.mem_fns.realloc_cb,
+ &fns.mem_fns.free_cb);
+ fns.lock_fns.lock_locking_cb = CRYPTO_get_locking_callback();
+ fns.lock_fns.lock_add_lock_cb = CRYPTO_get_add_lock_callback();
+ fns.lock_fns.dynlock_create_cb = CRYPTO_get_dynlock_create_callback();
+ fns.lock_fns.dynlock_lock_cb = CRYPTO_get_dynlock_lock_callback();
+ fns.lock_fns.dynlock_destroy_cb = CRYPTO_get_dynlock_destroy_callback();
+ /* Now that we've loaded the dynamic engine, make sure no "dynamic"
+ * ENGINE elements will show through. */
+ engine_set_all_null(e);
+
+ /* Try to bind the ENGINE onto our own ENGINE structure */
+ if(!ctx->bind_engine(e, ctx->engine_id, &fns))
+ {
+ ctx->bind_engine = NULL;
+ ctx->v_check = NULL;
+ DSO_free(ctx->dynamic_dso);
+ ctx->dynamic_dso = NULL;
+ ENGINEerr(ENGINE_F_DYNAMIC_LOAD,ENGINE_R_INIT_FAILED);
+ /* Copy the original ENGINE structure back */
+ memcpy(e, &cpy, sizeof(ENGINE));
+ return 0;
+ }
+ /* Do we try to add this ENGINE to the internal list too? */
+ if(ctx->list_add_value > 0)
+ {
+ if(!ENGINE_add(e))
+ {
+ /* Do we tolerate this or fail? */
+ if(ctx->list_add_value > 1)
+ {
+ /* Fail - NB: By this time, it's too late to
+ * rollback, and trying to do so allows the
+ * bind_engine() code to have created leaks. We
+ * just have to fail where we are, after the
+ * ENGINE has changed. */
+ ENGINEerr(ENGINE_F_DYNAMIC_LOAD,
+ ENGINE_R_CONFLICTING_ENGINE_ID);
+ return 0;
+ }
+ /* Tolerate */
+ ERR_clear_error();
+ }
+ }
+ return 1;
+ }
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